1. Field of the Invention
This invention relates to a portable planing machine for use in the woodworking and metal working arts to remove surface distortions and reduce thicknesses of material with a minimum and predictable loss of material.
2. Description of the Prior Art
There has been an ever-growing use of portable power tools by craftsmen in both the woodworking and metal working arts. Portable planing machines have also been known before, but some of them were supported directly by the work piece. Hence, some of the prior art portable power planes tended to distort the work piece or followed the distortions already present in the work piece. One example of such prior art is shown in the Skolnik U.S. Pat. No. 1,641,645, which appears to be a combination of a jack plane and a modified router having a series of four vertically-supported cutters. This Skolnik plane is supported directly by the work piece.
Another such portable planing machine that is supported directly by the work piece is described in the Beggs U.S. Pat. No. 1,319,557. This patent has a motor with a horizontal shaft that drives both a front and rear horizontal planing roller, on which the machine is supported.
Another prior art patent is Svendsen U.S. Pat. No. 1,139,383, which shows a log supported between two sawhorses. These sawhorses also carry a pair of parallel adjustable rails which extend the length of the log. The rails form a track on which is supported a rail car with double flanged wheels which ride the track. The rail car includes a motor with a horizontal shaft that drives a belt to power a horizontal rotary plane that is vertically adjustable. The log is subject to distortions, as it is suspended between two distant supports. Likewise the two rails are also subjected to distortions as the rail car travels back and forth.
The next prior art patent is Coleman U.S. Pat. No. 2,454,992, which is usable with a butcher's meat block to cut away the top surface and provide a new working surface. A trackway is attachable at the opposite sides of the meat block, and it supports a carriage that is provided with a motor having a vertical shaft with a circular saw blade for re-surfacing the meat block. The carriage also is provided with a vertical attachment or accessory for driving a sanding disk.
A patent in an unrelated and non-analogous art is the Westman U.S. Pat. No. 1,647,066, which shows a resurfacing machine for an ice skating rink. This machine has a frame supported by a pair of rear runners and a front motor-driven tractor wheel. The machine has a electric motor for driving the front wheel by means of a rope drive. The motor has a horizontal shaft that is coupled to a series of four interconnected cutter heads for shaving off the top surface of the ice. Each of the two runners of the machine is individually vertically adjustable, but again the machine is supported directly on the work piece.
The principal object of the present invention is to provide a portable planing machine for use on a work bench on which the work piece is fixdly supported. The planing machine is freely movable on the work bench, and the weight of the machine and its cutting action does not tend to distort the work piece.
A further object of the present invention is to provide a portable planing machine of the class described which is supported independently of the work piece, and does not follow the distortions that are inherent in the work piece.
A further object of the present invention is to provide a portable planing machine of the class described with means for guiding the machine as it passes over the work piece.
A still further object of the present invention is to provide a method of planing a work piece using a portable planing machine on a work bench, so as to remove the surface distortions with a minimum loss of material, and reduce the thickness of material in an accurate, predictable amount.